Prevention - The Key to Limb Salvage

Aksone Nouvong, DPM discusses the conservative approach to ulcer management and the indications and risks of the prophylactic surgical approach. Dr Nouvong reviews data that supports the positive outcomes of a prophylactic surgical approach to ulcer management.

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Aksone Nouvong
has nothing to disclose.

Lecture Transcript

Male Speaker: To wrap with our final talk, I think it’s probably as important as anything else that we've discussed. Our role as podiatrists is prevention. Prevention of these tragic complications, prevention of recurrent complications. Primary, secondary and even tertiary prevention. So I've asked Dr. Aksone Nouvong to come back and discuss the Key to Limb Salvage which I believe is really preventing something. Let's welcome back Dr. Nouvong. Thank you.

Aksone Nouvong: Yes. Thank you for welcoming me back. So in terms of prevention, I won't go through all the data of diabetes and all the complications of diabetes, but we know that diabetes leads to ulcerations and ulcerations can lead to amputation. So our goal is actually to prevent ulcerations and hopefully prevent the amputations. Before we can basically prevent ulcerations, it's important for us to understand how we develop ulcerations and Reiber actually discussed the triad of classes of ulceration. The main triad as we know neuropathy, deformity, and trauma, basically minor repetitive trauma. Unfortunately, we can't really prevent all neuropathy. In terms of deformity, can we prevent deformity? We can't prevent the structural deformity. What we can do is we can reduce some of this deformity. In reducing some of this deformity, we can potentially prevent some of these traumatic injuries. How can we prevent diabetic foot ulcers or how can we prevent reoccurrence of diabetic foot ulcers? As Dr. Hadi and all the other presenters discussed earlier, there are ways in which we can accommodate our patients to reduce ulcerations and reduce recurrence. Some of the ways that we can do it is to modify their shoes, have appropriate inserts, brace, CRO Walker which is discussed earlier. And if a patient already has an ulceration, the use of a total contact cast or instant total contact cast. There's been minor studies that looked at silicon injections, unfortunately not a lot of good results. Something else that Dr. LaPorta and also Dr. Sage discussed is education. That's an important aspect to reduce ulcerations and reoccurrence of ulcerations on diabetic patients. Another area in which we should also discuss is multidisciplinary team. That's really important to prevent but more importantly once the patient developed an ulcer, a multidisciplinary approach is going to be very useful in preventing infections and also amputation. The area which I'm going to focus on today is actually prophylactic surgery in order to one, prevent either ulceration, or two, prevent reoccurrence of ulceration. When shall we consider prophylactic surgery for our patients? Well, it's important to consider prophylactic surgery on a patient when one, we fail conservative therapy, or two, there's a recurrence of ulceration, three, there is a preulcerative lesion in which we want to prevent ulceration from forming. And also any rigid deformity that cannot be accommodated. What do I need to consider when I'm considering prophylactic surgery? Well, I need to know, number one, when is it indicated for me to do these procedures. Number two, are these procedures effective. Number three, what are some of the risks associated with these procedures that I'm considering. And number four, what does the literature say in terms of supporting any particular procedure. Before we actually discuss any particular procedure, I think it's really important for us to remember this classification system for diabetic foot surgery. This is a system that was developed by Armstrong and Frykberg. It's basically a classification going from classification one through four. And as you go from class one through four, the risks and comorbidities associated with this is much higher. Class one is an elective procedure and these are procedures that are done on diabetic patients who have no evidence of neuropathy. The risk with this procedure is actually pretty minimal and they're very similar to patients who don't have diabetes. Class two procedures are considered prophylaxis. Class two are done in patients who have neuropathy but they do not have any open lesion. Class twos are done in patients to either prevent an ulceration or prevent recurrence. Class three procedures are curative. Those are for patients who have neuropathy or they have an open lesion and you're trying to cure or correct the open lesion. Class four are the emergent. Again, as I discussed earlier it is associated with the highest risk in terms of morbidity. What is our goal of prophylactic surgery? Well, the goal is to, as discussed before, prevent ulcers which hopefully will prevent re-ulcers and/or amputation.

[05:00]

Our goal is to actually correct underlying structural deformity. Basically you want to reduce the pressure point or what you're going to basically have is a surgical offloading. As previous presenters discussed also, sometimes you actually just want to create a plantar foot so that you can fit these patients into proper shoe gear or bracing. You hope that the result of your surgery is to create stability, create a better functioning foot and also have a better alignment. Individual procedures you can consider. When should you consider digital procedure? Well, you should consider digital procedures when there's an ulcer at the tip of the toe or when there's an ulcer at the dorsal DIPJ or PIPJ. I won't go to the etiology because I know you know them already. But what are some procedures that can be done with the digit. Well, if it's a flexible digit, you can actually do soft tissue procedures that includes tenotomy, capsulotomy, tendon transfer or tendon lengthening. However, the digit is a rigid deformity you must do an osseous procedure whether it's an osteopathy or arthrodesis. As stated, are these effective? What are the risks? What does the literature state? Well, there was a study that was done by Kearney that looked at the safety of tendon transfers to healing toes. What they actually found out was 98% of the patients who undergone these procedures actually heal their ulcer. Then the recurrence rate for this procedure is only 12% compared to other literature reports of recurrence. Then the infection rate for these patients are very similar to what's been reported in the literature. Their conclusion was that tenotomy for digital ulceration is actually quite safe and has very little risk. Another study that was done by Armstrong basically looked at the dangers of foot surgery. They actually again looked at digital arthroplasty to determine whether it was effective, what was the risk of these procedures. They actually noted that patients who had digital ulcer who underwent arthroplasty had very similar infection as patients who are nondiabetic. As you can see here, zero percent for nondiabetic, zero percent for diabetics that had no evidence of ulcer. However, as stated earlier by other presenters, patients who have ulcers who undergo surgery do have a higher risk of developing infection. The risk with this procedure if there's an open lesion is a higher infection rate. What they concluded was that this procedure is safe and have little low risk for infection unless there's an open sore. In terms of hallux and first MTPJ procedures, when are this indicated. Well, these are indicated when there's a sub hallux IPJ ulcer or first metatarsophalangeal joint ulcer. Again, I won't belabor the etiology as I know we know them all. What are some of the procedures that can be done in patients with hallux IPJ ulcers or first metatarsophalangeal ulcers? You can do an HIPJ arthrodesis or an arthroplasty. You can do a condylectomy to resect the prominence. You can do a plain type of surgery. You can also do sesamoidectomies for those ulcers that are sub first metatarsophalangeal joint. You can do a MTPJ or metatarsal head resection or a Keller type of procedure. When doing these procedures, some things that you should consider. You can perform these procedures from a dorsomedial aspect like you're doing a bunion surgery. However, if you have an ulcer sub metatarsal, you can potentially approach it from a plantar aspect so that you can resect out the ulcer at the same time. If you're going to consider doing a sesamoidectomy of both tibia and fibular sesamoid, you may want to consider doing HIPJ fusion so that you can prevent hallux malleus. Are these procedures effective? Are they safe and what does the literature say? Well, this study here, it's an Armstrong study. It looked at the efficacy of first metatarsophalangeal joint arthroplasty. Again, what they found out with these procedures show that the recurrence rate is significantly lower than using standard of care alone to heal all these ulcers. Also, the amputation rate was about half as much as those who underwent standard of care alone. The infection rate as you can see here is very similar to patients who had standard of care also. In conclusion, the first metatarsophalangeal joint arthroplasty is effective, is safe, and it can reduce recurrence and amputation. For lesser metatarsal procedure, I think Dr. Hadi also touchbase on this also. The indication as to when you should do lesser metatarsal procedure is of course if you have ulcers, plantar lesser metatarsal heads.

[09:59]

In terms of procedures, what are some procedures that you can do to either cure the ulcer and/or prevent recursive ulcer. You can do a condylectomy, you can do a metatarsal osteotomy, including shortening or elevating those that are plantarflexed by using a V or dorsal base wedge. You can also do a metatarsal head resection with approach from the dorsal aspect or from a plantar aspect. You can also do solitary metatarsal head resection, however, if you’re going to be resecting more than two metatarsal, it is recommended that you do a panmetatarsal head resection. As discussed earlier by multiple presenters, a TAL is also important as an adjunctive procedure to reduce forefoot and midfoot pressure. Again, are these effective? What are the risks and what does the literature say? Well, Griffin actually did a study on metatarsal head resection diabetic foot ulcers. They actually found out that the healing rate was actually pretty short, approximately 2.4 months to heal ulcerations. Again, their infection and complication postoperatively is actually pretty low at 2.9. However, [indecipherable] [11:07] actually discussed the risk of panmetatarsal head resection. They noted that that would cure the ulcer, there was a high recurrence rate with panmetatarsal head. Also Giurini did another study on panmetatarsal head resection and they noted that they had an overall success rate of 97% when they did a panmetatarsal head versus doing a TMA on their patients. Panmetatarsal head resection seems like a viable procedure to do to reduce ulceration or reduce recurrence. Then their study, they had very low risk. They had zero amputation. As discussed also earlier, TAL is very important, either as a single procedure and/or as an adjunctive procedure. The indications for TAL is obviously ulcer of the forefoot or an equinus as Dr. LaPorta discussed very well earlier. A TAL reduce pressure at the forefoot, will also reduce pressure at the midfoot. Now the goal of the TAL based on studies by Lavery and Armstrong is that you’d want the forefoot peak pressure to be less than 65 Newtons per centimeter squared. TALs can be done with basically [indecipherable] [12:23] incisional, two medials, one lateral or two laterals and one medial. Is this effective and what are the risk and what does the literature say? Well, in terms of TALs, another Armstrong study show that doing a TAL reduce the forefoot peak pressure by approximately 27%. However, after six months postsurgery, the peak pressure did return, however, the ulcers did not recur. Another study that was done here by Muller was that one of the very few randomized clinical trial. He actually did a TAL, but a TAL in addition to a TCC. He found that TALs along with a TCC actually reduce recurrence and reduce ulceration significantly more than just doing a TCC alone. Again, they concluded that doing a TAL, in addition to a TCC decreased healing time, reduced recurrence and had very low complication rate. In terms of midfoot procedure, the indications are mainly for recurring ulcer and it’s oftentimes more for instability of the midfoot and these are usually secondary to Charcot and I won’t go through this as I knew that Dr. LaPorta and Dr. Sage was going to be going over Charcot already. But again, in terms of procedures, there’s multiple procedures that you can do. Something to consider is doing a TAL as an adjunctive combined procedure to reduce these recurring forefoot pressures. When doing all these procedure, something you might want to consider is if there is a presence of an ulcer, what are some of your options? Well, you can choose to do it one of two ways. You can have the ulcer heal secondarily or you can excise the ulcer and heal it primarily. If you’re going to excise the ulcer when you’re doing this reconstruction, it’s really important that there are no signs of infection, no signs of ischemia and that you have enough skin to actually close. If you’re going to do secondary closure, there are different methods in which you can utilize to help, including negative pressure wound therapy. You can use a flap. You can use an autologous graft and/or synthetic grafts. Then in terms of considering your incision approach, try to save an ulcer if you can unless you’re actually excising the ulcer itself. If you are excising the ulcer, excise the ulcer and take it off the field so that when you work on your osseous, you don’t have any contaminants.

[15:01]

Then when you do excise your ulcer, especially with a large ulcer, make sure that you close the ulcer before you correct your deformity. Because once you correct your deformity, you may not have enough tissue residual to close your ulcers. So, in terms of whether you want to do secondary wound healing or primary excise your ulcer, which one is better? Well, Katie Bloom actually did a study on single stage procedure and they noted that single stage procedure actually showed same result in terms of infection, but it actually reduced the risk of having to take the patients back to the OR and also it’s a reduced cost for the patient in general. So when approaching your patient, if you’re going to consider doing any of these prophylactic surgery, again, we’ll put there multidisciplinary approach, consider the patient’s comorbidity, check for infection, vasculature, and also blood glucose as presenters have discussed earlier. I’m going to put these next two slides up just to show you that there were two studies that were done by Dane Wukich and colleagues that looked at infection in diabetic patients. Though they did not just look at diabetic foot with ulcers, they looked at patients who underwent any type of foot surgery. They noted patients who had neuropathy had a higher risk of infections in general. When you’re doing these procedures, please note that they do have a higher risk of infections in general and both of Dane Wukich’s paper stated that there is a higher risk of infection in patients with neuropathy, and that’s one of the highest predictor. In summary, so when is it indicated for prophylactic surgery? What’s indicated when you fail conservative therapy and/or when you cannot accommodate these rigid deformities, two, are they effective. Yes, the literature has shown that they’re effective in reducing pressure and ulcer, reducing recurrence. Then what are some of the risks? Well, some of the risks as stated before are postop infection and does the literature support these procedures? The answer is yes. Thank you.